root@fdpi:/etc/apt/trusted.gpg.d# add-apt-repository ppa:amnezia/ppa
More info: https://launchpad.net/~amnezia/+archive/ubuntu/ppa
Press [ENTER] to continue or ctrl-c to cancel adding it
gpg: keybox '/tmp/tmposi0invi/pubring.gpg' created
gpg: /tmp/tmposi0invi/trustdb.gpg: trustdb created
gpg: key 4166F2C257290828: public key "Launchpad PPA for Iurii Egorov" imported
gpg: Total number processed: 1
gpg: imported: 1
Warning: apt-key is deprecated. Manage keyring files in trusted.gpg.d instead (see apt-key(8)).
gpg: no valid OpenPGP data found.
assist please with this issue